Epilepsy, Migraines May Have Family Ties

Jan. 8, 2013 -- People with epilepsy have a higher risk for migraines, and now new research offers evidence of a genetic link between the two conditions.

The study confirmed that having a strong family history of epilepsy is a strong risk factor for migraine headaches.

Epilepsy, Migraines, and Genes

When researchers studied about 500 families that included two or more members with epilepsy, they found that people with the largest number of close relatives with seizures also had the highest migraine risk.

Those with three or more close relatives with seizure disorder had more than double the risk for migraine with aura -- headaches with additional symptoms such as nausea or sensitivity to sound or light.

By following families, the researchers were able to show that the link between epilepsy and migraine was due to shared biology and not some other cause, says researcher Melodie R. Winawer, MD. She is an assistant professor of neurology at Columbia University in New York City.

"There are many reasons two diseases occur together, but it has not really been clear until now that these two diseases are genetically linked," she says.

Not All Seizures Have Genetic Cause

Winawer and colleagues at Columbia University analyzed data from an ongoing genetic study of epilepsy families in the U.S., Canada, Argentina, Australia, and New Zealand.

The study represents the largest collection of families with multiple members with epilepsy ever assembled, and a main goal is to determine how genes contribute to epilepsy risk.

Winawer explains that there are many kinds of epilepsy, and many people with the condition do not have family members who are afflicted.

Some people begin to have seizures after experiencing a blow to the head, for example.

But she says that studying families at strong genetic risk for seizure disorders could lead to a better understanding of epilepsy, and risk for migraine.

The analysis, which appears in the journal Epilepsia, included 730 epilepsy patients in the study from 501 families.

Epilepsy Drugs Prevent Migraines

Neurologist Nathan B. Fountain, MD, says the study makes a good case that shared genes help explain the higher incidence of migraines in people with epilepsy.

Fountain directs the epilepsy program at the University of Virginia School of Medicine, and he serves on the advisory board of the Epilepsy Foundation.

He says the genetic link could also explain why anti-seizure drugs like Depakote, gabapentin, and Topamax help prevent migraines or lessen their severity in some, but not all people with migraines.

He adds that the search for common genes that link epilepsy and migraines could lead to better strategies to treat or even prevent both disorders.

"Family-based population studies like this one represent a whole new way of doing research," he says. "There is no telling what we can learn from them in the future."